Fixing apparatus and image forming apparatus

Abstract

A fixing apparatus for fixing an toner image transferred onto a paper sheet, including: a fixing roller having a heater and an elastic layer on an external circumference surface thereof; a fixing belt driven by the fixing roller; a pressuring member which forms a nip portion between the fixing roller and the fixing belt; a separating member being arranged in a down stream of the pressuring member in a conveyance direction of a paper sheet, and being arranged to press the fixing belt; a pressing member which presses an edge of the separating member in a direction to which the fixing belt is pressed, and changes a position of the separating member relative to the fixing roller; and a plurality of adjusting members being provided in a longitudinal direction of the separating member and being arranged to adjust a position of the pressing member.

1. An image forming apparatus for forming an image on a paper sheet, comprising:
 an image forming section for forming a toner image; and 
 a fixing apparatus which fixes the toner image transferred onto the paper sheet, the fixing apparatus comprising:
 a fixing roller including a heater and an elastic layer on an external circumference surface thereof; 
 a fixing belt driven by the fixing roller; 
 a pressuring member which forms a nip portion for fixing the toner image on the paper sheet between the fixing roller and the fixing belt by making the fixing belt press the fixing roller from an inner circumference surface side of the fixing belt and; 
 a separating member arranged in a downstream side of the pressuring member in a conveyance direction of the paper sheet, and arranged to press the fixing belt from the inner circumference surface side so as to cause elastic deformation of the elastic layer of the fixing roller; 
 a plurality of pressing members provided in a longitudinal direction of the separating member, the pressing members pressing an edge of the separating member in a pressing direction in which the fixing belt is pressed and changing a position of the separating member relative to the fixing roller; and 
 a plurality of adjusting members provided in a longitudinal direction of the separating member, and located at locations respectively corresponding to the pressing members, the adjusting members respectively adjusting positions of the pressing members, 
 wherein at least one of the separating member and each pressing member has a slant surface, which is originally formed, at a position where the separating member and the pressing member contact each other. 
 
 
     
     
       2. The image forming apparatus according to  claim 1 ,
 wherein one of the separating member and each pressing member is slidable on the slant surface formed in the other one of the separating member and each pressing member, and 
 wherein the position of the separating member is changed in the pressing direction by adjusting the position of each pressing member in a perpendicular direction that is perpendicular to the pressing direction. 
 
     
     
       3. The image forming apparatus according to  claim 2 ,
 wherein a female screw is formed at each pressing member in the perpendicular direction, an external screw screwed together with the female screw is provided at each adjusting member, and each pressing member is moved and changed position in the perpendicular direction by rotating the external screw. 
 
     
     
       4. The image forming apparatus according to  claim 1 , wherein each adjusting member comprises a cam. 
     
     
       5. A fixing apparatus which fixes a toner image transferred onto a paper sheet, the fixing apparatus comprising:
 a fixing roller including a heater and an elastic layer on an external circumference surface thereof; 
 a fixing belt driven by the fixing roller; 
 a pressuring member which forms a nip portion for fixing the toner image on the paper sheet between the fixing roller and the fixing belt by making the fixing belt press the fixing roller from an inner circumference surface side of the fixing belt and; 
 a separating member arranged in a downstream side of the pressuring member in a conveyance direction of the paper sheet, and arranged to press the fixing belt from the inner circumference surface side so as to cause elastic deformation of the elastic layer of the fixing roller; 
 a plurality of pressing members provided in a longitudinal direction of the separating member, the pressing members pressing an edge of the separating member in a pressing direction in which the fixing belt is pressed and changing a position of the separating member relative to the fixing roller; and 
 a plurality of adjusting members provided in a longitudinal direction of the separating member, and located at locations respectively corresponding to the pressing members, the adjusting members respectively adjusting positions of the pressing members, 
 wherein at least one of the separating member and each pressing member has a slant surface, which is originally formed, at a position where the separating member and the pressing member contact each other. 
 
     
     
       6. The fixing apparatus according to  claim 5 ,
 wherein one of the separating member and each pressing member is slidable on the slant surface formed in the other one of the separating member and each pressing member, and 
 wherein the position of the separating member is changed in the pressing direction by adjusting the position of each pressing member in a perpendicular direction that is perpendicular to the pressing direction. 
 
     
     
       7. The fixing apparatus according to  claim 6 ,
 wherein a female screw is formed at each pressing member in the perpendicular direction, an external screw screwed together with the female screw is provided at each adjusting member, and each pressing member is moved and changed position in the perpendicular direction by rotating the external screw. 
 
     
     
       8. The fixing apparatus according to  claim 5 , wherein each adjusting member comprises a cam. 
     
     
       9. An image forming apparatus for forming an image on a paper sheet, comprising:
 an image forming section for forming a toner image; and 
 a fixing apparatus which fixes the toner image transferred onto the paper sheet, the fixing apparatus comprising:
 a fixing roller including a heater and an elastic layer on an external circumference surface thereof; 
 a fixing belt driven by the fixing roller; 
 a pressuring member which forms a nip portion for fixing the toner image on the paper sheet between the fixing roller and the fixing belt by making the fixing belt press the fixing roller from an inner circumference surface side of the fixing belt; 
 a separating member arranged in a downstream side of the pressuring member in a conveyance direction of the paper sheet, and arranged to press the fixing belt from the inner circumference surface side so as to cause elastic deformation of the elastic layer of the fixing roller; 
 a plurality of pressing members provided in a longitudinal direction of the separating member, the pressing members pressing an edge of the separating member in a pressing direction in which the fixing belt is pressed and changing a position of the separating member relative to the fixing roller; and 
 a plurality of adjusting members provided in a longitudinal direction of the separating member, and located at locations respectively corresponding to the pressing members, the adjusting members respectively adjusting positions of the pressing members after the separating member and the pressing members are assembled into the fixing apparatus without disassembling the pressing members and the separating member from the fixing apparatus. 
 
 
     
     
       10. The image forming apparatus according to  claim 9 , wherein at least one of the separating member and each pressing member has a slant surface, which is originally formed, at a position where the separating member and each pressing member contact each other. 
     
     
       11. The image forming apparatus according to  claim 10 ,
 wherein one of the separating member and each pressing member is slidable on the slant surface formed in the other one of the separating member and each pressing member, and 
 wherein the position of the separating member is changed in the pressing direction by adjusting the position of each pressing member in a perpendicular direction that is perpendicular to the pressing direction. 
 
     
     
       12. The image forming apparatus according to  claim 11 ,
 wherein a female screw is formed at each pressing member in the perpendicular direction, an external screw screwed together with the female screw is provided at each adjusting member, and each pressing member is moved and changed position in the perpendicular direction by rotating the external screw. 
 
     
     
       13. The image forming apparatus according to  claim 9 , wherein each adjusting member comprises a cam. 
     
     
       14. A fixing apparatus which fixes a toner image transferred onto a paper sheet, the fixing apparatus comprising:
 a fixing roller including a heater and an elastic layer on an external circumference surface thereof; 
 a fixing belt driven by the fixing roller; 
 a pressuring member which forms a nip portion for fixing the toner image on the paper sheet between the fixing roller and the fixing belt by making the fixing belt press the fixing roller from an inner circumference surface side of the fixing belt; 
 a separating member arranged in a downstream side of the pressuring member in a conveyance direction of the paper sheet, and arranged to press the fixing belt from the inner circumference surface side so as to cause elastic deformation of the elastic layer of the fixing roller; 
 a plurality of pressing members provided in a longitudinal direction of the separating member, the pressing members pressing an edge of the separating member in a pressing direction in which the fixing belt is pressed and changing a position of the separating member relative to the fixing roller; and 
 a plurality of adjusting members provided in a longitudinal direction of the separating member, and located at locations respectively corresponding to the pressing members, the adjusting members respectively adjusting positions of the pressing members after the separating member and the pressing members are assembled into the fixing apparatus without disassembling the pressing members and the eparating member from the fixing apparatus. 
 
     
     
       15. The fixing apparatus according to  claim 14 , wherein at least one of the separating member and each pressing member has a slant surface, which is originally formed, at a position where the separating member and each pressing member contact each other. 
     
     
       16. The fixing apparatus according to  claim 15 ,
 wherein one of the separating member and each pressing member is slidable on the slant surface formed in the other one of the separating member and each pressing member, and 
 wherein the position of the separating member is changed in the pressing direction by adjusting the position of each pressing member in a perpendicular direction that is perpendicular to the pressing direction. 
 
     
     
       17. The fixing apparatus according to  claim 16 ,
 wherein a female screw is formed at each pressing member in the perpendicular direction, an external screw screwed together with the female screw is provided at each adjusting member, and each pressing member is moved and changed position in the perpendicular direction by rotating the external screw. 
 
     
     
       18. The fixing apparatus according to  claim 14 , wherein each adjusting member comprises a cam. 
     
     
       19. An image forming apparatus for forming an image on a paper sheet, comprising:
 an image forming section for forming a toner image; and 
 a fixing apparatus which fixes the toner image transferred onto the paper sheet, the fixing apparatus comprising:
 a fixing roller including a heater and an elastic layer on an external circumference surface thereof; 
 a fixing belt driven by the fixing roller; 
 a pressuring member which forms a nip portion for fixing the toner image on the paper sheet between the fixing roller and the fixing belt by making the fixing belt press the fixing roller from an inner circumference surface side of the fixing belt and; 
 a separating member arranged in a downstream side of the pressuring member in a conveyance direction of the paper sheet, and arranged to press the fixing belt from the inner circumference surface side so as to cause elastic deformation of the elastic layer of the fixing roller; 
 a pressing member provided in a longitudinal direction of the separating member, the pressing member pressing an edge of the separating member in a pressing direction in which the fixing belt is pressed and changing a position of the separating member relative to the fixing roller; and 
 an adjusting member provided in a longitudinal direction of the separating member, and located at a location corresponding to the pressing member, the adjusting member adjusting a position of the pressing member, 
 wherein at least one of the separating member and the pressing member has a slant surface, which is originally formed, at a position where the separating member and the pressing member contact each other, 
 wherein one of the separating member and the pressing member is slidable on the slant surface formed in the other one of the separating member and the pressing member, and 
 wherein the position of the separating member is changed in the pressing direction by adjusting the position of the pressing member in a perpendicular direction that is perpendicular to the pressing direction, and 
 wherein a female screw is formed at the pressing member in the perpendicular direction, an external screw screwed together with the female screw is provided at the adjusting member, and the pressing member is moved and changed position in the perpendicular direction by rotating the external screw. 
 
 
     
     
       20. A fixing apparatus which fixes a toner image transferred onto a paper sheet, the fixing apparatus comprising:
 a fixing roller including a heater and an elastic layer on an external circumference surface thereof; 
 a fixing belt driven by the fixing roller; 
 a pressuring member which forms a nip portion for fixing the toner image on the paper sheet between the fixing roller and the fixing belt by making the fixing belt press the fixing roller from an inner circumference surface side of the fixing belt and; 
 a separating member arranged in a downstream side of the pressuring member in a conveyance direction of the paper sheet, and arranged to press the fixing belt from the inner circumference surface side so as to cause elastic deformation of the elastic layer of the fixing roller; 
 a pressing member provided in a longitudinal direction of the separating member, the pressing member pressing an edge of the separating member in a pressing direction in which the fixing belt is pressed and changing a position of the separating member relative to the fixing roller; and 
 an adjusting member provided in a longitudinal direction of the separating member, and located at a location corresponding to the pressing member, the adjusting member adjusting a position of the pressing member, 
 wherein at least one of the separating member and the pressing member has a slant surface, which is originally formed, at a position where the separating member and the pressing member contact each other, 
 wherein one of the separating member and the pressing member is slidable on the slant surface formed in the other one of the separating member and the pressing member, and wherein the position of the separating member is changed in the pressing direction by adjusting the position of the pressing member in a perpendicular direction that is perpendicular to the pressing direction, and 
 wherein a female screw is formed at the pressing member in the perpendicular direction, an external screw screwed together with the female screw is provided at the adjusting member, and the pressing member is moved and changed position in the perpendicular direction by rotating the external screw.